diff -r 000000000000 -r 6474c204b198 gfx/src/nsTransform2D.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/gfx/src/nsTransform2D.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,23 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsTransform2D.h"
+
+void nsTransform2D :: TransformCoord(nscoord *ptX, nscoord *ptY) const
+{
+  *ptX = NSToCoordRound(*ptX * m00 + m20);
+  *ptY = NSToCoordRound(*ptY * m11 + m21);
+}
+
+void nsTransform2D :: TransformCoord(nscoord *aX, nscoord *aY, nscoord *aWidth, nscoord *aHeight) const
+{
+  nscoord x2 = *aX + *aWidth;
+  nscoord y2 = *aY + *aHeight;
+  TransformCoord(aX, aY);
+  TransformCoord(&x2, &y2);
+  *aWidth = x2 - *aX;
+  *aHeight = y2 - *aY;
+}